Many industrial systems require counters at various stages therein for retaining a count of operations performed. These counters are often mechanical or electromechanical in nature and have the disadvantages of being unreliable, costly, and bulky. However, they have the advantage of retaining a count during periods of electrical shutdown or power outages. Electronic counters with optical readouts would often be preferable for the reasons that they are highly reliable, relatively inexpensive, and much smaller in size. Such counters include a memory and a visual readout display. The memories are "volatile" which means that they function only so long as power is on and data is lost when power is off. This makes them undesirable for any use in which a count must be maintained over such power out periods.
It is a primary object of the present invention to provide a system which combines the advantages of both types of counter but avoids their disadvantages. The manner in which this and other objects are achieved will be more apparent from the following description and appended claims.